1. Field of the Invention
The present invention relates to a method for optimizing ciprofloxacin treatment of anthrax-exposed patients according to the patient""s characteristics. More particularly, the invention optimizes the survival outcome of a ciprofloxacin treatment for an anthrax-exposed patient, with the ciprofloxacin dose regimen adjusted according to the patient""s characteristics, including age, body weight, gender, and renal function.
2. Description of the Related Art
The effectiveness of ciprofloxacin treatment for anthrax may significantly rely on the adequacy of the antibiotic regimen. The regimens of ciprofloxacin currently recommended for treating anthrax are based only on animal survival data and minimum pharmacokinetic information [Physician""s Desk Reference, 2001]. Due to the lack of human data reviewed in the prior art, a fixed regimen has been recommended for all patients, namely 500 mg twice daily oral dose.
Even with the fact that the effectiveness of ciprofloxacin against most other infectious organisms is over 80% [Physician""s Desk Reference, 2001] at the recommended doses, the survival rate of anthrax patients treated with the drug remains relatively low (50xcx9c60% in the US 2001 outbreak [CDC MMWR Weekly, 2001]).
Thus, it is desirable to improve and optimize the currently recommended ciprofloxacin regimen in order to increase the patient survival rate. It is therefore necessary to determine the survival rates of anthrax-exposed patients treated with different ciprofloxacin regimens and select the optimal treatments. One possible approach to obtain the survival data is to conduct human experiments to investigate the effectiveness of various dose regimens in different patient populations. However, this approach is not practical due to the ethical reason.
3. Information Disclosure
Ciprofloxacin and its quinolone family are a series of potent antimicrobial agents with a broad spectrum of antimicrobial activities. The quinolone family is active against a variety of human and veterinary pathogens, including both gram-positive and gram-negative bacteria. Ciprofloxacin is disclosed in U.S. Pat. No. 4,670,444, issued Jun. 2, 1987 to Bayer Aktiengesellschaft.
The present invention seeks to overcome the drawbacks inherent in the prior art by providing new methods for improving and optimizing the ciprofloxacin regimen for treating anthrax-exposed patients.
Therefore, one object of the present invention is to provide a method to optimize the survival rate of ciprofloxacin treatment for anthrax in different patient populations.
It is known that a complete bacteria eradication by ciprofloxacin usually occurs within several days after the initiation of the antibiotic treatment. Therefore, during the first few days of the antibiotic treatment, the patients may remain culture-positive. Since the deaths of the patients infected with anthrax are associated with the presence of the bacteria in the patient""s body, it is plausible that the mortality rate of the ciprofloxacin-treated and yet culture-positive patients is similar to the mortality rate of the controlled patients who receive no effective treatment, if significant amounts of anthrax bacteria remain in patients from both treated and controlled groups.
Therefore, the mortality rate of the ciprofloxacin-treated patients can be estimated from the mortality rate of the controlled patients, if the duration of exposure to the anthrax bacteria in the former can be determined from the bacteria eradication rate of the ciprofloxacin regimen.
It has been unexpectedly discovered, during the investigations of the mortality rate of various ciprofloxacin regimens for treating anthrax-exposed patients, that the mortality rate among patients is highly variable depending on the patient characteristics. It has also been discovered that, the mortality rate of anthrax in certain patient populations can be reduced by up to 2 folds, compared to the treatment effects of the currently recommended regimens, if the patients are treated with an optimized ciprofloxacin regimens. It has further been discovered that the optimal ciprofloxacin regimen for treating anthrax is between 625 mg to 1500 mg twice daily oral dose for some patient populations and the precise optimal regimen is dependent on the patient""s characteristics.
The mortality rate is equal to (1xe2x88x92survival rate).